title: The seasonality of bipolar affective disorder: comparison with a primary care sample using the Seasonal Pattern Assessment Questionnaire.
abstract: BACKGROUND
  In contrast with recurrent unipolar depression, relatively little is known about the seasonality of depressive episodes in bipolar affective disorder (BAD).
  
  
  METHODS
  We compared responses on the Seasonal Pattern Assessment Questionnaire (SPAQ) between a cohort of 183 patients with BAD and a large sample of patients in primary care (N=4746). Comparisons were adjusted for age and gender.
  
  
  RESULTS
  27% of the BAD patients fulfilled SPAQ criteria for Seasonal Affective Disorder (SAD. This gave an adjusted odds ratio of 3.73 (95% confidence intervals 2.64 to 5.27) in comparison with the rate among the primary care samples. Global seasonality scores were significantly higher among BAD patients (adjusted mean difference 1.73, 95% CI 0.97 to 2.49, p<0.001).
  
  
  CONCLUSIONS
  The SPAQ was originally designed as a screening instrument rather than as a case-finding instrument.
  
  
  CONCLUSIONS
  Vigilance for seasonal symptom recurrence in BAD may be important with regard to management and relapse prevention.
authors.affiliation: Royal Cornhill Hospital, Aberdeen, UK.
authors.forename: Allen J
authors.initials: AJ
authors.lastname: Shand
authors.forename: Neil W
authors.initials: NW
authors.lastname: Scott
authors.forename: Seonaid M
authors.initials: SM
authors.lastname: Anderson
authors.forename: John M
authors.initials: JM
authors.lastname: Eagles
mesh_terms: D000293:Adolescent; D000328:Adult; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000453:epidemiology* / Q000523:psychology; D015331:Cohort Studies; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000706:statistics & numerical data; D008875:Middle Aged; D011320:Primary Health Care / Q000706:statistics & numerical data; D011594:Psychometrics / Q000706:statistics & numerical data; D016574:Seasonal Affective Disorder / Q000175:diagnosis* / Q000453:epidemiology* / Q000523:psychology; D012621:Seasons; D011795:Surveys and Questionnaires; D006113:United Kingdom; D055815:Young Adult